yes, it will have a slightly taller side wall. Granted, the difference in height will only be about 4.5mm. I seriously doubt that 1/5th of an inch will be even noticeable.
just curious, why do you want the taller side wall? just to fill in the gap in the wheel well?
with the pro springs the front is already low enough, dont want it any lower. I will put the 235s on the back and the 245s on the front, what do you think.
That is not a good idea. Tire sizes are expressed in ratios. 235, 245, etc. tells you the width of a tire in millimeters. The reason 245's are taller than 235's when you are talking about the same aspect ratio, here 45's, is that the aspect ratio, e.g. 60, 50, 45, 40, etc., is an expression of width vs. height. In other words, the only numbers in a tire size that are constant are the width, e.g. 235, and the rim diameter, e.g. 17, 18, 20, etc. Given these facts, the bottom line is that the 235's on the rear would be narrower than the 245's on the front, which is a look that I would assume you are not seeking.